1. Field
The subject matter described herein relates generally to circuit breaker accessories and, more particularly, to lock assemblies for circuit breaker accessories.
2. Related Art
It is known in the art to provide molded case circuit breakers for electrical systems. The circuit breaker is operative to disengage the electrical system under certain operating conditions. The use of accessories such as, for exemplary purposes only, motor operators to allow the motor-assisted operation of electrical circuit breakers is well known. The motor operator allows the circuit breaker to be operated remotely and to be opened, closed or reset after tripping of the circuit breaker.
The motor operator is typically secured to the top of a circuit breaker housing. A lever within the motor operator mechanically interacts with a circuit breaker operating handle, which extends from the circuit breaker housing. The lever is operatively connected to a motor within the motor operator. The motor drives the lever, which, in turn, moves the operating handle to operate the circuit breaker. The operating handle is moved between “on”, “off”, and “reset” positions, depending on the rotational direction of the motor.
A plurality of buttons external to the motor operator controls electrical current to the motor. The rotational direction of the motor is changed depending on which of these buttons is selected by operating personnel. Thus, the operating personnel can select one button to place the operating handle in the “on” position, and another button to place the operating handle in the “off” or “reset” positions.
When the handle is moved to the “on” position, electrical contacts within the circuit breaker are brought into contact with each other, allowing electrical current to flow through the circuit breaker. When the handle is moved to the “off” position, the electrical contacts are separated, stopping the flow of electrical current through the circuit breaker. When the handle is moved to the “reset” position, an operating mechanism within the circuit breaker is reset, as is necessary after the operating mechanism has tripped in response to an overcurrent condition in the electrical circuit being protected by the circuit breaker.
In one example, the circuit breaker accessory such as the motor operator described above may include one or more lockout devices such as padlocks or keyed cylinders for preventing unauthorized operation of the motor operator. In one example, the lockout devices may disable the motor operator mechanism in any suitable manner. Generally the padlocks are inserted through an aperture in a piece of, for example, the motor operator mechanism that protrudes through the motor operator housing or cover. The keyed cylinders are generally installed by opening the housing of, for example, the motor operator and assembling the keyed cylinder onto the housing.
It would be advantageous to be able to install a keyed cylinder onto a circuit breaker accessory in the field without removing or opening the housing of the circuit breaker accessory.